In bottle treatment machines, a conveyor system is provided for transporting bottles, such as PET bottles, between various stations. In the conveyer system, multiple conveying paths can be provided, between which the bottles are to be transferred for distributing or sorting. Alternatively or additionally, a variable capacity storage can be incorporated into the conveyor system, which in the event of failure or malfunction of a station temporarily stores the bottles delivered to a station and not received at the same rate, or for a faster receiving rate supplies enough bottles, in order to create a time buffer within which ideally the malfunction is eliminated, so that the bottle treatment machine is continuously operable. In both cases, it is standard to use the bottle carrier chain simultaneously as a tension member to which the conveying movement is applied. For a change of path between different conveying paths each with a bottle chain, it is necessary to take the bottles off a bottle carrier chain and to transfer them onto the other bottle carrier chain. This requires a number of tension members and bottle carrier chains. Due to the dual task of bottle carrier chains being used as tension members, namely the load-bearing function and the driving function, such bottle carrier chains are complex, expensive and prone to damage. In the second case of a storage having the bottle carrier chain fulfilling the drive function and the load-bearing function, it is necessary during deflection to release the bottle carrier chain from a guide and insert it into another. In addition, the bottle carrier chain, fulfilling the driving movement along the guides and the load-bearing function, must be of a great length, for instance as an endless loop.
A conveyor system of a bottle treatment machine is known from DE 10 2004 053 663 A, where, in the storage formed as a storage tower, two neighboring guides are disposed in a spiral-shaped manner in which at least part of an endless loop of the bottle carrier chain is guided and driven, and to which a carriage with two reverse-image transfer guides is movably arranged in order to be able to vary the capacity of the storage as required. The bottle carrier chain is directly driven along the guides, is a special link chain, and carries plate-like bottle carriers or bottle grippers on the upper side. In the respective transfer area, the bottle carrier chain is released from the guide by mechanical means of the transfer guide, guided and deflected in the transfer guide and by mechanical means again inserted into the other guide. This results in considerable strain, so that the bottle carrier chain is very stabile and heavy duty also due to the considerable load, and relatively high driving power is required which in turn subjects the bottle carrier chain to considerable local tension stress. The bottle carrier chain also acting as tension members can, for example, also have frictionally engaged contact between the bottles, the guides and the like, leading to contamination and wear of the bottles.
A conveyor system of a cigarette processing machine is known from EP 0 581 143 B, in which either a single chain-type conveyor element is used simultaneously for initiating the drive movement and for carrying the load, or a load-bearing conveyor element is driven independently in each of two separate guides. A variable capacity storage is integrated into the conveyor system, which has at least one transfer guide for deflecting the conveyor flow from one guide onto the other guide. In the case of only a single endless conveyor element, it is in the transfer area released from a guide, transferred and re-inserted into the other guide. In the second case with the two conveyor elements drivable independently of each other in the two guides, the transfer guide is designed as a bridge-shaped conveyor element which receives the flow of cigarettes from a conveyor element, transfers it and conducts it to the other conveyor element.
A goods-conveyor system having a variable capacity storage is known from EP 1 161 391 B, in which two belt carrier chains are driven and guided in two adjacent guides which at the same time fulfill a load-bearing function. In the transfer area, a rotatable conveyor disc is moveably arranged between the guides and along them, which at the same is driven in rotation by both belt carrier chains in order to be able to receive goods, transfer and again load them onto the other belt carrier chain.
A substantially straight-lined conveyor system for the same or similar objects is known from EP 1 232 974 B, which in piece goods processing are treated in multiple processing steps. In the conveying path, a guide for a belt carrier chain is disposed, which fulfills only a load carrying and conveying function. On both sides of the guide, toothed belt drives or drive wheels are arranged there, which are driven at a desired speed of circulation corresponding to the conveying speed, and transfer this speed of circulation to the load carrier chain with which they overlap for a certain distance. Transfer of the drive speed is effected by magnetic effect in that the belt drives or the drive discs carry series of permanent magnets, and magnetized armature elements or magnets are arranged at the individual belt carriers of the belt carrier chain.